We seeded our food plots on September 23rd and all that week we had moisture on the ground. I wasn't able to fertilize before seeding and I had planned on doing it right after seeding but the rain kept us out of property and wasn't able to do so. I am heading to our place this weekend but would like to know if it is too late to fertilize?

Point has been made most importantly you need a good rain on it soon after it is laid down. Or it will burn the plant if touching but over time the fertilizer will release into the air. In other words waste of money.

Doesn't it depend on the type of fertilizer you spread if it burns your crops? I was told that once it’s up and growing, while the soil is still warm, around mid/late November, put out 70lbs per acre of ammonium sulfate (21-0-0) for our plot. This will give us an additional 15lbs of N per acre. I wouldn't think that this small amount would tend to burn the crops. Am i mistaken?

Doesn't it depend on the type of fertilizer you spread if it burns your crops? I was told that once it’s up and growing, while the soil is still warm, around mid/late November, put out 70lbs per acre of ammonium sulfate (21-0-0) for our plot. This will give us an additional 15lbs of N per acre. I wouldn't think that this small amount would tend to burn the crops. Am i mistaken?

I'm not as experienced as others on here that's why I came to the green screen for advice and answers. I'm sure a fellow tbh'er can shed light on your question.

If you didn't get your soil analyzed and told you need a certain amount of specific elements per acre. Go get some 13-13-13, wait until you know it's going to rain in the next day, then go spread it. There should be no burning.

Yes any fert can burn if not watered in almost immediately. Yes its better to wait for a strong chance of rain before applying any fert. But unfortunately a lot of us dont live near our hunting grounds and weather forcasts are not that good anyway most often.
BUT, the only plants the fert will burn if not watered in are the ones the fert pellets are actually TOUCHING. So...best case is to wait for rain but on field like urs ul loose very little crop by burning due to individual plants have germinated with soil between them for fert to lay on and wait for rain to dissolve them. Its not like you have a solid layer of crop with fert just laying on top of plants.
It is true that you will loose some to the air, but its better than no fert at all.
Also, id go with something balanced as a "starter" fert as suggested above.
Straight ammonium sulfate is nothing but nitrogen and is very corrosive with high salt index and prob has the best chance for burning of anything you could put out. But it will dang sure produce growth once it gets wet.
Trip 13 as also Stated above is a good choice and easy formulation to get cheap at any feed store.

We seeded our food plots on September 23rd and all that week we had moisture on the ground. I wasn't able to fertilize before seeding and I had planned on doing it right after seeding but the rain kept us out of property and wasn't able to do so. I am heading to our place this weekend but would like to know if it is too late to fertilize?

Wait for a good rain chance and get after it. I would do it as soon as possible while we have the warm growing conditions. Watch for army worms too. Plants might get a slight burn but using dry will cut down on that.

I mix my fertilizer and seed together. This yr it will 1200 lbs of oats and 2000 lbs of 30-10-10 on 10 acres

Have done it many times. Sorry it is of no help to OP now but for future reference.

If you are at the field AFTER it has rained try this. Go get 1-2 bags of fertilizer, pour into clean 5 gal bucket and hand throw it out. Place a stick in the ground at the ideal point you would want the buck to stop for an ethical shot and fertilizer a 50 ft circle there. The plants will be “sweeter” at that location. Has worked for me in the past